Food is often irradiated with either x rays or electron beam

Food is often irradiated with either x rays or electron beams to help prevent spoilage. A low dose of 5-75 kilorads (krad) helps to reduce and kill inactive parasites, a medium dose of 100-400 krad kills microorganisms and pathogens such as salmonella, and a high dose of 2300-5700 krad sterilizes food so that it can be stored without refrigeration.If electrons of RBE 1.50 are used instead of x rays, what would be the dose in Gy ?

Solution

The relation between REM (rontgen equivalent man ) and RBE is

              REM = (rad ) ( RBE )

since RBE for x - rays is 1

            dose in rad for x-rays is 2300-5700 krad

for electrons , RBE is 1.5 . so the dose in rad for electrons is

                = ( 2300/ 1.5 ) - ( 5700 / 1.5 ) k rad

                =1533 krad - 3800 krad

100 rad = 1 Gy. so

    dose of electrons in Gy is

             15330 Gy - 38000 Gy